New insight into the process of generation of new neurons in the adult brain

| Newsline

Researchers at Sahlgrenska Academy at the University of Gothenburg, Sweden, in collaboration with research groups in Finland, Canada, and Slovenia, have discovered a novel and unexpected function of nestin, the best known marker of neural stem cells.

In the developing brain, the 3 main cell types, specifically neurons, astrocytes and oligodendrocytes, are generated from neural stem cells. In some parts of the brain, such as the hippocampus, the brain region involved in learning and memory, new neurons are being added to the existing neuronal circuitry even in the adulthood when severe restriction of neuronal differentiation occurs.

Using mice deficient in nestin, a protein that is a component of the part of the cytoskeleton known as intermediate filaments or nanofilaments, the research team led by Prof. Milos Pekny showed that nestin produced in astrocytes has an important role in inhibiting neuronal differentiation. They linked this regulatory function of nestin to the Notch signaling from astrocytes to neighboring neural stem cells. Thus, surprisingly, nestin does not control the generation of neurons by acting within neural stem cells, but indirectly by regulating the neurogenesis-inhibitory Notch signals that neural stem cells receive from astrocytes, important constituents of the neurogenic niche.